Array process is one of stages in the manufacture of a thin film transistor liquid crystal display (TFT-LCD) device. In the array process, a thin film transistor array circuit needs to be formed on a glass substrate. Since the quality of the array circuit directly decides the quality of a TFT-LCD screen, testing of the array circuit becomes an important process in the manufacture of a TFT-LCD device.
As shown in FIG. 1, an array substrate 100, in early stage of the manufacture, includes: a display region 101, a lead wire region 102 and a peripheral region 103. A plurality of first pixel units for display formed by intersecting gate lines and data lines are provided in the display region 101, and each first pixel unit corresponds to one thin film transistor. The lead wire region 102 is configured to provide electric connections of signals for necessary signal elements in the display region 101, for example, an input wire for data line signal in the display region 101 may be included therein. Since the TFTs in the respective pixel units in the display region 101 are disturbed by other patterns and layers, their performance can hardly be detected, and as a result, a detecting region 104 is further provided in the peripheral region 103 of the substrate. As shown in FIG. 2, a plurality of pixel units formed by intersecting gate lines and data lines are provided in the detecting region 104, and each pixel unit corresponds to one thin film transistor (TFT), which is used for detecting characteristics of TFTs on the substrate. Specifically, the respective electrodes of the TFT for detection are connected to a test device through lead wires, as shown in FIG. 3. After the array substrate and a color filter substrate are fitted to form a display panel, the peripheral region 103 is generally cut off.
In actual manufacturing process, there are some differences between the manufacture of the TFTs in the detecting region and the manufacture of the TFTs in the display region. For example, densities of the TFTs and signal lines thereof in the display region are larger than those in the detecting region, and process environments in which the TFTs are respectively formed in the two regions differ a lot, which results in significant difference in electrical characteristics caused by different processes between the TFTs in the two regions, and therefore, the relevant characteristics of the manufactured TFTs in the display region significantly differ from those of the TFTs in the detecting region. Further, the characteristics of the TFTs in the detecting region 104 are nonuniform, and the test results differ significantly.
Therefore, by detecting the relevant characteristics of the TFTs in the detecting region 104, the relevant characteristics of the TFTs in the display region cannot be reflected accurately, thus reducing accuracy of the detection.